Study on the Calculation method of the Coal and Gas Outburst Threshold

Abstract

The four undetermined parameters of the temperature-pressure-adsorption equation (TPAE) were obtained by regression of the series isothermal adsorption data of the measured middle-rank deformed coal and normal coal. The unit isosteric adsorption enthalpy (UIAE) was obtained. According to the negative value of the UIAE, adsorption is an exothermic process, desorption is an endothermic process. The coal and gas outburst threshold (OT) is defined as the product of the firmness coefficient and the unit isosteric desorption enthalpy (UIDE) to show the combined effect of adsorption thermodynamics and tectonic stress. The UIDE difference between the two coals was from 1.91 times expanded to OT difference of 5.74 times.